data_global _chemical_name_mineral 'Terskite' loop_ _publ_author_name 'Pudovkina Z V' 'Chernitsova N M' _journal_name_full 'Doklady Akademii Nauk SSSR' _journal_volume 316 _journal_year 1991 _journal_page_first 645 _journal_page_last 649 _publ_section_title ; Crystal structure of terskite Na4Zr[H4Si6O18] ; _database_code_amcsd 0012483 _chemical_formula_sum 'Na4 Zr Si6 O18' _cell_length_a 14.195 _cell_length_b 14.750 _cell_length_c 7.511 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 1572.625 _exptl_crystal_density_diffrn 2.702 _symmetry_space_group_name_H-M 'P n c 2' loop_ _space_group_symop_operation_xyz 'x,y,z' 'x,1/2-y,1/2+z' '-x,1/2+y,1/2+z' '-x,-y,z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv Na1 0.75540 0.99760 0.52500 0.01039 Na2 0.21670 0.23690 0.97000 0.02406 Na3 0.00000 0.00000 0.90500 0.01254 Na4 0.50000 0.00000 0.05600 0.01760 Na5 0.70660 0.22730 0.01600 0.01773 Zr 0.25370 0.99740 0.00020 0.01368 Si1 0.58530 0.13100 0.75530 0.01089 Si2 0.38810 0.13870 0.30010 0.00963 Si3 0.36680 0.15380 0.71400 0.00811 Si4 0.86720 0.15330 0.28650 0.00899 Si5 0.89010 0.13820 0.69840 0.00785 Si6 0.08350 0.13160 0.24560 0.01026 O1 0.49900 0.12900 0.29800 0.01659 O2 0.47000 0.12300 0.78900 0.01798 O3 0.85300 0.13200 0.49200 0.01558 O4 0.35000 0.12900 0.50300 0.01153 O5 0.34900 0.23700 0.24200 0.00899 O6 0.85400 0.23700 0.78500 0.01507 O7 0.11500 0.26200 0.71900 0.01178 O8 0.28600 0.10600 0.82200 0.01431 O9 0.33500 0.06000 0.19100 0.01216 O10 0.78500 0.10100 0.17000 0.00887 O11 0.83500 0.05700 0.80500 0.01254 O12 0.97100 0.12400 0.22100 0.01368 O13 0.00300 0.13200 0.72000 0.01292 O14 0.61400 0.23700 0.74200 0.01140 O15 0.63600 0.07500 0.91100 0.01456 O16 0.61200 0.08800 0.55000 0.01735 O17 0.13400 0.08000 0.08400 0.01482 O18 0.11700 0.09200 0.42700 0.01963